The Prevention Research Branch (PRB), an intramural research group of the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) is conducting a longitudinal component of the Health Behavior in School-Ages Children (HBSC) study. This longitudinal study is called NEXT. The NEXT study collects information on adolescent health status and health behaviors. A nationally-representative cohort of approximately 2,800 U.S. 10TH grade students was recruited academic years under the HBSC longitudinal study. African-American youth were oversampled to provide better population estimates and to provide an adequate sample to examine racial/ethnic differences in longitudinal predictors of health, health behaviors, and health behavior change. Self-report of health status, health behaviors, and health attitudes are collected by in-school and online surveys. Anthropometric and neighborhood data are also collected for all NEXT participants. A subsample called NEXT Plus includes approximately 275 normal weight and 275 overweight or obese participants who were recruited from the NEXT cohort. The additional assessments performed with the NEXT Plus subsample include: objective assessment of physical activity, sedentary behavior, and sleep; biological and genetic markers including those for obesity, cardiovascular disease, and metabolic syndromes. In addition, we will be tracking fasting blood glucose, HbA1c, total cholesterol, triglycerides, LDL-C, HDL, C-reactive protein, uric acid, cotinine, height, weight, waist circumference, blood pressure, and nutrient intake in the NEXT Plus participants.